What "Building history" means, and why we don't rush it
Scroll to the bottom section of the board and you'll sometimes see routes labeled "Building history," shown dimmer than the rest. That's not a bug or a placeholder — it's an honest state we show on purpose, for a specific reason.
The rule
A route needs at least 10 distinct days of accumulated price history, spanning at least 14 days, before we'll classify it as a deal — or rule it out as "priced, not a deal." A median built on 2 or 3 days of data isn't statistically meaningful yet; calling something a 25% discount off a 2-day median is a much weaker claim than the same math off a real 30-day trailing median. Below that threshold, we'd rather say "not enough data yet" than dress up a shaky number as a confident one.
Why it's visually dimmed, not just labeled
An earlier version of the board treated every card the same regardless of how much history backed it — a genuinely misleading presentation, since "no real signal yet" and "priced and not currently a deal" look identical to a reader skimming the page. The dimmed treatment (technically a .grid-dimmed style) exists specifically so a route without enough history reads as visually different at a glance, not just in the fine print.
No backfilling, ever
A missing day — a fetch that didn't return a result — is simply skipped, never backfilled with a guessed or repeated price. A synthetic number would quietly corrupt the exact median every other calculation on the site depends on. Full details on that median in how we rank deals.